Thermal surgical tool

Abstract

An electrical conductor, such as a wire or catheter, which is coated circumferentially with a ferromagnetic material in a selected region, is fed from a high frequency alternating current source. The ferromagnetic material has a quick response in heating and cooling to the controllable power delivery. The ferromagnetic material can be used for separating tissue, coagulation, tissue destruction or achieving other desired tissue effects in numerous surgical procedures.

The invention claimed is: 
     
       1. A thermal surgical tool, comprising:
 a first arm having a first proximal end, a first distal end, a first side and a second side, the first distal end spaced from the first proximal end along a length of the first arm, the first side and the second side spaced laterally apart from one another along a width of the first arm over at least a portion of the length of the first arm, each of the first and the second sides extending between the first proximal end and the first distal end, wherein the width is perpendicular to the length; 
 a second arm having a second proximal end and a second distal end, the second distal end spaced from the second proximal end along a length of the second arm, the second distal end movable selectively toward and away from the first distal end; and 
 a ferromagnetic heater on the first arm, the ferromagnetic heater including an electrical conductor and a ferromagnetic coating covering a portion of the electrical conductor, the ferromagnetic coating having a first edge and a second edge spaced laterally apart from one another along the width of the first arm, the first edge positioned adjacent to the first side of the first arm, the second edge positioned adjacent to the second side of the first arm, and the first edge positioned relative to the second edge such that as the ferromagnetic coating extends toward the first distal end a distance measured from the first edge toward the second edge along the width of the first arm decreases. 
 
     
     
       2. The thermal surgical tool of  claim 1 , further comprising a power source and wherein the electrical conductor is elongate and wherein the power source, when in use, is attached to the electrical conductor independent of the ferromagnetic coating such that passing power through the electrical conductor heats the ferromagnetic coating. 
     
     
       3. The thermal surgical tool of  claim 1  wherein the ferromagnetic coating includes a plurality of sections disposed on the electrical conductor. 
     
     
       4. The thermal surgical tool of  claim 1 , further comprising a thermal insulator disposed between the electrical conductor and the ferromagnetic coating. 
     
     
       5. The thermal surgical tool of  claim 1 , further comprising a non-stick coating disposed upon the ferromagnetic coating. 
     
     
       6. The thermal surgical tool of  claim 1 , further comprising a biocompatible material covering at least a portion of the ferromagnetic coating. 
     
     
       7. The thermal surgical tool of  claim 1 , wherein the ferromagnetic coating is circumferentially disposed about the electrical conductor. 
     
     
       8. The thermal surgical tool of  claim 1 , further comprising an electrical circuit configured to deliver oscillating electrical energy to the electrical conductor by electrically connecting to the electrical circuit with the first section and second section of the electrical conductor independent of the ferromagnetic coating. 
     
     
       9. The thermal surgical tool of  claim 8 , wherein the electrical circuit comprises an impedance matching circuit. 
     
     
       10. The thermal surgical tool of  claim 1 , comprising a second electrical conductor and a second ferromagnetic coating covering the second electrical conductor. 
     
     
       11. The thermal surgical tool of  claim 1  wherein the ferromagnetic heater is attached to a surface of the first arm. 
     
     
       12. The thermal surgical tool of  claim 1  wherein the ferromagnetic heater is at least partially embedded within the first arm. 
     
     
       13. The thermal surgical tool of  claim 1 , further comprising a sensor, the sensor, when in use, monitors at least one of the ferromagnetic coating, the electrical conductor, or tissue, if any, disposed adjacent to the first arm or the second arm. 
     
     
       14. The thermal surgical tool of  claim 1  wherein the ferromagnetic heater is disposed on a surface of the first arm which faces an opposing surface of the second arm. 
     
     
       15. The thermal surgical tool of  claim 1  wherein at least one of the first arm or the second arm defines a pointed distal tip. 
     
     
       16. The thermal surgical tool of  claim 1 , further comprising a second ferromagnetic heater on the second arm, the second ferromagnetic heater including a second conductor having a first section and a second section, and a second ferromagnetic coating covering a portion of the second electrical conductor between the first section and the second section. 
     
     
       17. The thermal surgical tool of  claim 1  wherein the ferromagnetic coating covers the first arm between the first edge and the second edge. 
     
     
       18. The thermal surgical tool of  claim 1  wherein the first edge of the ferromagnetic coating has a shape which corresponds to a shape of the first side of the first arm, and the second edge of the ferromagnetic coating has a shape which corresponds to a shape of the second side of the first arm. 
     
     
       19. The thermal surgical tool of  claim 12  wherein the ferromagnetic coating covers the first arm between the first edge and the second edge. 
     
     
       20. The thermal surgical tool of  claim 1  wherein an entirety of the first edge and an entirety of the second edge both lie within a plane, the plane defined by the length and the width of the first arm.